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42 have had a celestial origin, and that the potent elements of which it is composed must have been mingled by an all-wise and beneficent Power.

We have resolved Fire into the phenomena of light and heat, and have separated the constituents of Air; let us now summon Water into our presence, and compel that supposed element to reveal its true nature.

Water, like Air, was once regarded as the origin of all things; indeed this belief in the universality of moisture may be said to have laid the foundation speculative philosophy among the Greeks.

Water exists in the three physical states—the solid, liquid, aëriform. By adding heat to liquid water we convert it into aëriform water, or steam; by abstracting heat from it, we change it into solid water, or ice; in either case the chemical composition of water remains unaltered.

We can demonstrate the compound nature of Water by analysis or by synthesis; in plainer language, by resolving it into its elements, or by forming it from its elements. Let us first see how its analysis may be effected.

Some chemical compounds, the red mercurial scales, for example, are decomposable by heat, but Water is merely vaporized by this potent agent. To overcome the attractive force or affinity which binds the elements of Water together, we must call in the aid of some substance which has a superlative affinity for one of these elements.